1. Field of the Invention
The present invention relates to a system and method for monitoring the departure of a child from a retail store or other area having an electronic article surveillance system.
2. Description of the Prior Art
A lost or abducted child is a parent's greatest fear. While shopping with a small child, a parent or guardian remains constantly on watch to make sure that the child does not wonder off. From the store's perspective, this constant concern presents a major distraction, leading to loss of sales. Many retail stores have installed a children's play area to minimize the shopping parent's distraction. These play areas do not effectively prevent a child from wandering unless the play area is supervised.
Alternative measures directed to solving the wandering child dilemma have been the subject of much investigation. Numerous devices have been disclosed over the years to tackle this problem. U.S. Pat. No. 5,848,567 to Colaianni discloses a leash adapted to attach a child to the guardian. U.S. Pat. No. 5,510,771 to Marshall employs a cable that alarms if it is broken. These devices put sever limitations on the mobility of child and guardian. U.S. Pat. No. 4,694,284 to Leveille et al. transmits an alarm signal when a collar is removed from a child. U.S. Pat. No. 5,617,074 to White discloses a button having a transmitter and adapted to be attached to a child's clothing or wrist strap. The button actuates an alarm if it is tampered with. Such devices may help deter abduction, but provide a less than satisfactory solution to the problem presented by a wondering child.
Generally, electronic devices designed either to monitor children within an enclosed area, or within the framework of an individual system. In the first case, the system alarms when the child leaves the monitored area. In the second case, the child wears a tag and the guardian carries a control unit. When the child strays too far from the unit, the distance between the two causes the sounding of an alarm carried by either or both of the control unit and the tag.
U.S. Pat. No. 5,337,041 to Friedman employs a tag worn by a child and adapted to be triggered by the guardian to sound an alarm when the child is out of sight. U.S. Pat. No. 5,307,763 to Arthur et al. places a loop antenna around the border of an area appointed for confinement of a child and tag alarms adapted to be worn by a child when appointed for transport outside the protected area. This device is expensive, requiring purchase of a monitoring system and wiring of an entire monitored area. U.S. Pat. No. 5,640,147 to Chek et al. discloses a tag adapted to be worn by a child. The tag is provided with a microphone and transmitter which enables a parent to listen in and thereby monitor the child's activity. These devices may help deter abduction, but they fail to solve the problem presented by the wondering child.
Numerous devices are adapted to trigger an alarm when a battery powered tag worn by the child exceeds a predetermined distance from a transmitter carried by the guardian. Representative of these devices are those disclosed by: DE Patent 19,608,348 to Whitehurst; U.S. Pat. No. 5,661,460 to Budzyna et al.; WO Patent 9,618,913 to Budzyna et al.; WO Patent 9,627,173 to Campana; WO Patent 9,614,625 to Edwards; U.S. Pat. No. 5,512,879 to Stokes; WO Patent 9,607,998 to Gerstenberger et al.; GB Patent 2,279,170 to Newton; U.S. Pat. No. 5,289,163 to Perez et al.; GB Patent 2,248,331; U.S. Pat. No. 4,899,135 to Gharariiran; U.S. Pat. No. 5,557,259 to Musa; U.S. Pat. No. 5,461,365 to Baringer et al. FR 2704345 to Gadi; GB Patent 2,276,025 to Bartwell; FR Patent 2,674,351 to Dal Bo et al; FR Patent 2,608,868 to Estienne; WO Patent 8,706,748 to Corwin et al.; GB2182183 to Garrett et al.; U.S. Pat. No. 4,598,272 to Cox; FR Patent 2,543,715 to Mayer; DE Patent 3,215,942 to Fuchshuber; GB Patent 1,496,945; U.S. Pat. No. 5,689,024 to Traxler; and U.S. Pat. No. 5,812,056 to Law. Retail stores oftentimes generate large amounts of electronic noise. Such noise typically eminates from point of sale equipment and electronic article surveillance systems. These devices frequently exhibit extreme performance variability with differing electronic noise environments. U.S. Pat. No. 5,629,678 to Gargano et al. employs a tag that is implanted in the child; and which has obvious shortcomings. In each of these devices there is imposed an additional restriction that impedes the performance thereof. The additional restriction requires that the store install special monitoring equipment or that the guardian carry a monitoring unit.
Additional variations of a child monitoring system have been disclosed. British Patent 2,291,303 to Duffy provides direction to a transmitter worn by the child. In U.S. Pat. No. 4,785,291, the tone changes with distance changes. U.S. Pat. No. 5,119,072 to Hemingway discloses a weak signal alarm with a microphone. U.S. Pat. No. 5,021,794 to Lawrence uses transmitter/receiver and works through the cellular phone system. GB Patent 2,218,245 to Hoyle et al. discloses a device that protects babies from unauthorized removal from a hospital. GB Patent 2,248,330 to Seeman uses infrared or sonic signals. WO Patent 8,703,404 to Royoux has LEDS indicating direction and distance. In each of these devices there is imposed the further requirement that the store install special monitoring equipment or the guardian carry a monitoring unit.
EP Patent 323,041 to Newman et al. uses a magnetic strip in a wrist or ankle strap to protect against unauthorized removal of an infant. This is one of the technologies used in electronic article surveillance (EAS) systems. Numerous EAS patents exists that employ a magnetic strip. Representative of these EAS patents is U.S. Pat. No. 4,553,136 to Anderson, et al. Unfortunately, devices utilizing EAS technology have a very short detection range, typically three feet, and suffer from a low detection rate. Such systems are also susceptible to false alarms.
When EAS systems are used, markers are attached to articles to be protected. The markers are responsive to an electromagnetic field generated at the store's exit by the EAS system's transmitter. Each marker must be removed or deactivated before an article to which it is affixed leaves the store. Otherwise, upon exiting the store, the marker disturbs the field. This disturbance is detected by the EAS system, and an alarm is triggered. U.S. Pat. No. 4,510,489 discloses a technology used in EAS systems that have been employed to protect infants from unauthorized removal from hospitals. EAS markers are generally inexpensive and operate as a passive device, without their own power. As a result, the operating range of EAS markers is limited and their detection rate, though acceptable for some applications, is much too low to assure protection of children.
Implementation of a child monitoring system within a retail environment in the conventional way would require the store to purchase and maintain a system. If the retail facility already possessed an EAS system, it would have to maintain both systems. This is a costly solution. Alternatively, with conventional child monitoring systems, protection of each child would require the responsible parent to provide his own individual system. The shear number of teachings directed to child monitoring systems and the consipcuous absence from the marketplace of such systems strongly suggests that the problem remains to be solved.
Accordingly, there remains a need in the art for a cost-effective system that exhibits an extremely high detection rate and which accurately and reliably monitors and protects against the unauthorized departure of children from retail stores.